From b3d9ce1c22334767f0dfd38e647dcd0c75799113 Mon Sep 17 00:00:00 2001
From: John Darrington <john@darrington.wattle.id.au>
Date: Tue, 8 Oct 2013 21:34:28 +0200
Subject: [PATCH] Provide home grown rl_echo_signal_char if readline does not
 provide it

---
 acinclude.m4                      |  5 +++--
 src/ui/terminal/terminal-reader.c | 33 ++++++++++++++++++++++++++-----
 2 files changed, 31 insertions(+), 7 deletions(-)

diff --git a/acinclude.m4 b/acinclude.m4
index ee7c9b0be6..bc4d5b9d37 100644
--- a/acinclude.m4
+++ b/acinclude.m4
@@ -124,8 +124,9 @@ AC_DEFUN([PSPP_READLINE],
     AC_MSG_CHECKING([how to link with libreadline])
     AC_MSG_RESULT([$LIBREADLINE])
     AC_SEARCH_LIBS([rl_outstream], [readline],
-        AC_DEFINE(HAVE_RL_OUTSTREAM, 1, [Define if the readline library provides rl_outstream.])
-    )
+        AC_DEFINE(HAVE_RL_OUTSTREAM, 1, [Define if the readline library provides rl_outstream.]))
+    AC_SEARCH_LIBS([rl_echo_signal_char], [readline],
+        AC_DEFINE(HAVE_RL_ECHO_SIGNAL_CHAR, 1, [Define if the readline library provides rl_echo_signal_char.]))
   else
     dnl If $LIBREADLINE didn't lead to a usable library, we don't
     dnl need $INCREADLINE either.
diff --git a/src/ui/terminal/terminal-reader.c b/src/ui/terminal/terminal-reader.c
index 2d72acf39c..b4eae73add 100644
--- a/src/ui/terminal/terminal-reader.c
+++ b/src/ui/terminal/terminal-reader.c
@@ -26,6 +26,7 @@
 #if HAVE_READLINE
 #include <readline/readline.h>
 #include <readline/history.h>
+#include <termios.h>
 
 static char *history_file;
 
@@ -107,14 +108,36 @@ terminal_reader_cast (struct lex_reader *r)
   return UP_CAST (r, struct terminal_reader, reader);
 }
 
-/* 
-   Older libreadline versions do not provide rl_outstream.
-   However, it is almost always going to be the same as stdout.
- */
-#if HAVE_RL_OUTSTREAM
+/* Older libreadline versions do not provide rl_outstream.
+   However, it is almost always going to be the same as stdout. */
+#if ! HAVE_RL_OUTSTREAM
 # define rl_outstream stdout
 #endif
 
+/* Similarly, rl_echo_signal_char is fairly recent.
+   We provide our own crude version if it is not present. */
+#if ! HAVE_RL_ECHO_SIGNAL_CHAR
+static void
+rl_echo_signal_char (int sig)
+{
+  struct termios t;
+  if (0 == tcgetattr (0, &t))
+    {
+      cc_t c = t.c_cc[VINTR];
+  
+      if (c >= 0  && c <= 'Z' - 'A')
+	fprintf (rl_outstream, "^%c", 'A' + c - 1);
+      else
+	fprintf (rl_outstream, "%c", c);
+    }
+  else
+    fprintf (rl_outstream, "^C");
+
+  fflush (rl_outstream);
+}  
+#endif
+
+
 static size_t
 terminal_reader_read (struct lex_reader *r_, char *buf, size_t n,
                       enum prompt_style prompt_style)
-- 
2.30.2